hello,
i jailbroke my ipad version 4.2.1 using redsnow and it was working fine and i downloaded a couple of games through ******. Last night i was downloading some application and i fell asleep. When i woke up i found an apple icon on my ipad with a small stuck up circle. I tried every thing to get rid of it but i couldnot. I connected it with i tunes but it doesnot recognize my ipad. I mean nothing happens when i connect it with itunes. I mistakenly deleted the earlier itunes with ipad firmware. Kindly advice. I would really appreciate an early response.

Put it in dfu mode an restore. Next time don't load any sources becides what comes on cydia. You just asking for trouble who knows what virus/whatever you could be downloading.

iClarified - iPhone - How to Put an iPhone Into DFU Mode