What is the best wheel I can purchase for my glider?

You definitely want to stay away from the wodent wheel. I have heard horror stories. There are a few different places you could get a good wheel from. Any of the following are good:

http://atticworx.com/

http://customchoicecruiser.all4gliders.com/

http://www.spinzoneglobal.com/

http://www.mygliderwheelsandmore.com/

Those are the few that I know of, I have a wheel from atticworx and I really love it. It's a stealth wheel and super quiet. I plan on purchasing one from spin zone as well.

I got mine from Spinzone Global and I am very pleased with their quality, so I can vouch for them.

Edit: They also have great customer service

I have 1 from spinzone and attic works. I like the one from attic works better due to the mounting I purchased will allow me to use the stand or hang on cage. Both are 12". I have the velociratpor. It has a replaceable sealed bearing and is water tight and can be submerged in water to clean. The spin zone has a replaceable bearing. I haven't had to lubricate the spin zone but it recommends not to submersible in water. So I take the wheel out of cage when I power wash it.