if the league is sanctioned, does it cost more?
There's an annual sanction fee that you have to pay, roughly around $20. It's usually per region. For example, if you want to join another league in another town, but the same county, you don't have to pay the sanction fee for that other league. Just let the league secretary know that you're already in another sanctioned league. If it's a different region, you may pay a discounted rate.
Does everyone have to be USBC members to join?
Yes. The league secretary will give all the forms to be filled out.
If my average is still low, is it better to not make the numbers official? heh
It's up to you. I've seen guys who throw hard & fast one or especially 2 handed and think they're good, just because they can throw a strike who have an average around the 130's. When I first started in a sanctioned league back in 2004, I had a 156 average. I now have a 202 average. My major mistake were trying to force the ball to what it wasn't supposed to do, rather than letting it do what it was designed to do. I would have done better knowing about this forum allot sooner. The nice thing is, you can see your progress on the USBC website. If you do happen to roll a 300, 11 strikes in a row, 800 series, and I think a 900 series, it will be shown on the USBC website. It's allot nicer to brag about it to your friends or your bowling buddies. Otherwise, you would have to carry around a printout of your achievement.
FYI, a book average is your average in the USBC member books, which can also be looked up at bowl.com.
Also, you can't use a spinner release in a sanctioned league.
I didn't know that. I would assume that a sanctioned league didn't care how you through the ball. I've seen different types of releases from 1 to 3 fingers being used, 1 or 2 handed, a backup ball as their regular strike release, and even one that spins backwards first then rolls forward.