I noticed that there's a library to access link textJena models from Sesame. Is there anything that works the other way around, say, if I want to access OWLIM-Lite from Jena?
I don't believe there is any general bridging component at the level of Sesame SAILs that connects it to Jena models, at least not something that is actively maintained.
However, OWLIM has its own Jena adapter that allows you to access it via the Jena API instead of the default Sesame API. It's relatively new and perhaps still a bit experimental, but it might be what you're after.
Of course, Sesame implements the SPARQL protocol, so you can access any Sesame repository via Jena/ARQ like any other SPARQL endpoint.