Ibm t61 turns on but all I get is a blank black

Hi,
This sounds rather bad. You're not even getting a "thinkpad" screen?
Try unplugging the power and removing the battery for a minute and attempt to power up again.
If it's still not starting, try removing the memory modules (if there are two, remove one and try powering up, then try to remove the other one). Although I seem to remember that newer thinkpads will still show thinkpad logo and attempt to POST even with bad memory (then throw an error), it's always worth a try.
If the above don't make any difference then I'm afraid most probably your motherboard has failed. In theory you could also try swapping the cpu-I've seen a cpu go bad ONCE in my several years of tinkering with laptops.
T61 is a current model-wouldn't it still be under warranty from lenovo? Might be worth checking the serial on their website. Otherwise it's time to search for T61 donor laptops on ebay - ordering a new motherboard from lenovo parts suppliers will most probably be far too expensive.
Good luck, hope you get it working again!
Raf