Im wondering if anyone knows of any products that would fix areas that have 'split' on my boat's drivers seat without having to hire someone to re-stitch.  I know they have those tear repair kits but this vinyl (i think its vinyl) appears to have came loose from the stitching and runs a good 10-12 inches long.  

Sorry, but the only real way to do it is to have it re-stitched.  If it were a rip somewhere else on the seat, you could patch it or use some type of kit, but it never really comes out the same.  You can stitch it yourself or if you know someone who is good with a sewing machine, but you have to get some marine grade thread which is pricey.

Get a big needle and go at it yourself, if it looks like crap, cut it and start over. If you just cant get it, hire someone.