I went through a vendor selection process last year and we chose http://tax.cchgroup.com as our vendor. We didn't do the integration in Perl, but they had some decent web API's to do what you want. We ruled out Taxware based on cost.

This product handles as much level of detail as you want to get. As others have noted, taxation is a very complex thing to implement correctly. It's not just a per-state thing. You can't even rely on state->county->city to remain the same across states as some states don't recognize that heirarchy. Throw on top of that, the fact that different products (food, clothing, pharmaceuticals, etc.) can each be taxed at a different rate at any point in a state's heirarchy and it tends to get REALLY crazy.