Welcome to pinstack.com asean!! Sorry it took so long to reply, today is a busy day on the stacks!
Please make sure when you are trying yo load ringers you are looking for midi ringers. My fav. site is www.freeringtoneheaven.com, but there are so many sites to choose from. Here is another, www.mobile41.com, ran my by good buddy and fellow stacker srl7741.
If you are interested in joining a stack group please click the Join Stack Groups link in my signature, i would be glad to have you in the Nextel and 7100 stack groups!