Welcome to the board and the fun of mountain biking. When you do get your bike, check out our ride schedule that starts up in the spring. On monday nights we have a beginner ride that alternates between Rocky Ridge Park and Lake Redman. The monday night ride is a great way to work up your skills in a beginner friendly environment as well as meet other riders. Other rides may appear as people post them. Hope to see you on the trails!
I don't have any specific recommendations for a bike, but there are many members with great bike knowledge.
Also (
shameless promotion begins), check out our trailwork schedule. This is another way to meet other riders as well as give back to the parks with your time and effort

You can also support YAMBA by becoming a member. You can join here
http://www.yamba.org/membership/membership.php which is the Join Us link on the main page.
Ray