I unfortunately was unable to find any links on this forum or on XDA that would help you in your pursuit of root. Being "like
" a fascinate and being "able
" to use fascinate roms and kernels are two very different things.
I would tell you with the utmost stress on the "DO NOT
" part, "DO NOT
flash any rom or kernel that is not specifically made for you phone, to your phone. If you do this, the odds of getting you a nice, new brick is almost assured.
I'm not trying to be a dick here, just trying to keep you from making a mistake that a lot of novice rooters make. The excitement of having this removed or that added, gets people to try to cut corners or improvise on things they shouldn't.
If I happen to come across something, I'll try to post it later.
Since you seem to have very little knowledge of what your trying to do, the following link might give you some insight to what rooting, kernels and roms are about. Its a lot of reading , but I don't think you can be over prepared.
While i I still suggest you do the reading, it seems that the Samsung Mesmerize and the Showcase may be similiar.
The forums here: http://androidforums.com/samsung-mesmerize/
The XDA site info: http://forum.xda-developers.com/forumdisplay.php?f=886