Check out Airhawk. There's no replacement for a good aftermarket seat, BUT, if that isn't an option- an Airhawk IS a fantastic solution. Easily doubled my ride time on my stock seat (before I finally bought the mustang seat)

 

I have been thinking about using these guys

http://www.meancitycycles.com/

I know it is suppose to already have a pretty comfy seat, but I got butt burn on my first long ride.

 

Mean City has done my wife's 500 seat and my Mustang 750 seat.
Great work and customer service.

 

Oh! Also, don't forget about Russel day-long! It's a custom made seat formed to your dimensions. I've yet to find a bad review for a Russel. I don't have one, but, it really seems like they are the best!

 

There's not a lot out there. Drifter seats can be adapted fairly easily, and I hear people talking about Mustang seats. I got a DIY one with my bike, and I've been reupholstering it in various styles to get it to work right for me. I think I'm one more iteration away from having it perfect, and let me tell you, it's been worth the trouble and then some!

 

Would like some info and pics of what you are doing to you seat .......

 

Sure, check it out here: http://www.vulcanforums.com/forums/showthread.php?t=35570

 

http://diymotorcycleseat.com/

I might tackle an overhaul on my seat this winter.

 

DIY MC Seat is a great site- I got a lot of great info there.

You can get closed sell foam from REI if nothing else- they sell "sitting pads" that are 1 inch by 18 by 18 or so of high-quality closed sell foam.