I'm sure there are many services that would do it for you. It's no different to converting vinyl though, very easy to do yourself.
Just connect the tape deck to the line in on your machine (you may need a USB audio in adaptor) and then find some software to record and away you go.
I recomend keeping the raw files (or flac/apple lossless/whatever lossless method you like) about so if you want to filter them differently in the future you do not have to either re-do the entire process of suffer the horrible degradation of using an mp3 as input in audio fiddling.