Visit
www.usfirsthost.com and click "Get Hosting" under "Navigation" to the left. It's free hosting to any and all FIRST teams that follow the rules. Have somebody on your team with experience setup the site or place in the comments that you need help building a site.
Don't get us wrong, having a team Myspace can help promote your team and FIRST in general by bringing in others from the network, but as a primary site it should be avoided for multiple obvious and previously stated reasons, including the whole most-schools-block-myspace thing.