The simplest answer to this question is that if you are a member of an institution that has a license to the, then (so long as you are on-site and have half-decent web access) that is by far the best way to search the texts of the Thesaurus Linguae Graecae.
(UPDATE: there appears to be a beta version of the PHI Greek inscriptions online at. This is currently free, although I cannot guarantee that it will remain so, or even remain available. We shall post more news on this when we learn it.)
If you do not have access to the online TLG, however, or if you are interested in searching one of thediscs of documentary papyri and inscritions (PHI 7.0) or Latin texts (PHI 5.3), then you should be aware that the CDs on which these texts are served do not contain software with which to read or search said data.
If you run a Windows PC (or a Classics Mac--OS 9 or lower) then many of the software applications listed on themay be appropriate. Most of these are commercial products that require purchasing, although some are cheap or even free. (Several tools are reviewed in a recent BMCR article at .)
If you run Mac OSX or Linux, then you may like to try the free search tool, which is not listed on the TLG page. MacOSX users may also be able to run the HyperCard software package Pandora using either the Classic system 9.2 emulator, or a HyperCard emulator such as (though I should disclose that I haven't managed to make the latter work yet, GB).
to be continued