I believe you have to post on the BAR thread (not checked anymore by JaGeX), and they'll review your account's status. If you qualify to come back into the game, you can pay to get back in (normally like $30 USD).
You've heard right, you can post your banned account name here http://services.runescape.com/m=forum/forums.ws?250,251,3,62411000. You'll just need an unbanned account with access to the forums, don't give jagex your sob story, they honestly don't care. Please bare in mind you'll experience harsh rollbacks, and most of the account's cash will be removed. Also you'll be required to buy 3 months worth of membership on the account, just to unlock it. You must add an additional one to get back in the game; members.