I hve a 500GB WD External HDD, wont detect?

i have a 500GB WD external HDD, when i connect it it gives me the usual sound but does not detect, i have opened the case and connected it as an internal slave, still would not detect, Checked the Bios it does not show up there either, I guess its fried. My question is, Is there anything we could do now (uming its not fried) and i have some very imp data on it, if i give it for recovery which by the way costs a gazzilion dollars with no guarantee of data recovery, will they be able to get the data??