Blackberry Data Plan?

[Vaudou]

I have a BB Bold 9700 with T-Mobile, but I don't have the data plan. I can use wifi, but of course that means no access on the road and what not. Also, for some reason, the connection seems weak with wifi, like I downloaded Pandora, installed it to my phone, but it somewhere along the lines it won't connect or uses too much data for wifi to handle or something, but I can't use it. I don't want to use the BB Enterprise Server because it'll cause additional charges or whatever.

So basically I'm asking: Is there anyway to have the full access of blackberry (i.e. App store, email, etc.) without getting a data plan?