This is dependent on TeX Live but does not require grep
:
tlmgr search --file '.*tikzlibrary.*\.code\.tex'
produces:
aobs-tikz:
texmf-dist/tex/latex/aobs-tikz/tikzlibraryoverlay-beamer-styles.code.tex
hobby:
texmf-dist/tex/latex/hobby/tikzlibraryhobby.code.tex
ocgx:
texmf-dist/tex/latex/ocgx/tikzlibraryocgx.code.tex
pgf:
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/circuits/tikzlibrarycircuits.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/circuits/tikzlibrarycircuits.ee.IEC.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/circuits/tikzlibrarycircuits.ee.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/circuits/tikzlibrarycircuits.logic.CDH.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/circuits/tikzlibrarycircuits.logic.IEC.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/circuits/tikzlibrarycircuits.logic.US.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/circuits/tikzlibrarycircuits.logic.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/datavisualization/tikzlibrarydatavisualization.3d.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/datavisualization/tikzlibrarydatavisualization.barcharts.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/datavisualization/tikzlibrarydatavisualization.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/datavisualization/tikzlibrarydatavisualization.formats.functions.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/datavisualization/tikzlibrarydatavisualization.polar.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/datavisualization/tikzlibrarydatavisualization.sparklines.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/graphs/tikzlibrarygraphs.basic.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/graphs/tikzlibrarygraphs.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrary3d.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryarrows.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryautomata.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarybackgrounds.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarycalc.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarycalendar.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarychains.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.footprints.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.fractals.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.markings.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.pathmorphing.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.pathreplacing.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.shapes.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarydecorations.text.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryer.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryfadings.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryfit.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryfixedpointarithmetic.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryfolding.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryfpu.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryintersections.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarylindenmayersystems.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarymatrix.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarymindmap.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarypatterns.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarypetri.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryplothandlers.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryplotmarks.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarypositioning.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryscopes.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshadings.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshadows.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.arrows.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.callouts.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.gates.logic.IEC.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.gates.logic.US.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.geometric.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.misc.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.multipart.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryshapes.symbols.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarysnakes.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryspy.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarysvg.path.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarythrough.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarytopaths.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibrarytrees.code.tex
texmf-dist/tex/generic/pgf/frontendlayer/tikz/libraries/tikzlibraryturtle.code.tex
texmf-dist/tex/latex/pgf/frontendlayer/libraries/tikzlibraryexternal.code.tex
pgf-blur:
texmf-dist/tex/latex/pgf-blur/tikzlibraryshadows.blur.code.tex
pgfplots:
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.colormaps.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.dateplot.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.external.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.groupplots.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.patchplots.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.polar.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.smithchart.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.statistics.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.ternary.code.tex
texmf-dist/tex/generic/pgfplots/libs/tikzlibrarypgfplots.units.code.tex
texmf-dist/tex/generic/pgfplots/oldpgfcompatib/pgfplotsoldpgfsupp_tikzlibraryexternal.code.tex
texmf-dist/tex/generic/pgfplots/oldpgfplotscompatib/tikzlibrarydateplot.code.tex
texmf-dist/tex/latex/pgfplots/libs/tikzlibrarypgfplots.clickable.code.tex
texmf-dist/tex/latex/pgfplots/libs/tikzlibrarypgfplotsclickable.code.tex
rulercompass:
texmf-dist/tex/latex/rulercompass/tikzlibraryrulercompass.code.tex
sa-tikz:
texmf-dist/tex/latex/sa-tikz/tikzlibraryswitching-architectures.code.tex
spath3:
texmf-dist/tex/latex/spath3/tikzlibrarycalligraphy.code.tex
texmf-dist/tex/latex/spath3/tikzlibraryknots.code.tex
tikz-bayesnet:
texmf-dist/doc/latex/tikz-bayesnet/tikzlibrarybayesnet.code.tex
tikzmark:
texmf-dist/tex/latex/tikzmark/tikzlibrarytikzmark.code.tex
Unlike David Carlisle's solution, though, this won't pick up stuff from the local texmf
tree.
[I think it is kind of neat you can do this with tlmgr
, though, so I'm posting it anyway.]