Ascendo Money is $30 but it comes with a free trial. its what i use and i love it. i would highly suggest giving it a trial run and see if you like it.
1 vote for JapLite, to find it Google Blackberry Freeware, someone asked the same question a couple weeks back, it was a member that worked in a bank, another member mentioned JapLite and he loved it so its got another vote from a member that works in the banking world.
I have been using Mobile Checkbook for the past several months now and have had no problems with it.
I initially purchased it from the shop crackberry software section. I believe it was between $12-$15.
At the time, I did not know about the aforementioned free checkbook app but will have to check it out.