Had car repaired in Feb 2004, issued check for service, ck run through
telecheck at that time & ck was good.  account was not balanced or
regularly monitored.  Rec'd call in Feb 2006 saying ck not processed;
couldn't find records & asked for copy since didn't even have ck #;
instead of ck copy, rec'd cert ltr demanding payment; wrote again
asking for ck info; rec'd by reg mail 3/20 & learned shop had
deposited ck in interim & ck ret'd 3/6/2006 marked sufficient funds;
now they've filed suit; are there any options for me?

It might depend on where you live but, as I see it, no.

Signing and presenting the cheque provides compelling evidence of your
acknowledgment of the debt.

So, in my view, you have no alternative but to pay up.

You say check was marked sufficient funds. That would mean they cashed
it and got there money. Unless this is a typo. If they got your money
I would shoot them a copy of the check (your bank should have it on
file). They will see they are in the wrong and back off there claim.
Also get a copy of it yourself so if you have to go to small claims
court you can show it to the judge and be case closed. If you meant to
say insufficient funds in your post then you would still liable for
money owed. There would be no time limit on when they can cash the
check unless stated in the contract or on the check. And that would
still be questionable.

Sorry, uncamike-ga, but if the cheque was returned to the presenter
then it would have been marked 'insufficient funds'.

I'm sure that this was a typo in the Question. 

Right Nathan?

Nathan2006-ga,
Your telegraphic style leaves a couple of questions open.

Did you receive a call from the repair company?  Did it then
subsequently try to deposit the check  - two years after it had been
issued?  marked "sufficient" or insufficient funds?  A two years old
check could have been returned for being "stale dated", despite there
being funds on the account.  If it had been presented and returned due
to insufficient funds, your bank would have debited the account with a
service charge.

Depending on the state where this occurred, the "statute of
limitation" might apply, but probably not, since the shop has filed a
suit.

But all that is, I feel, rather immaterial.  You had your car
repaired, wanted to pay for it at the time, and now have had two years
delay on actually having to do so.  If they have a case, fighting it
will cost you even more.
I would suggest negotiating with them immediately to pay the bill and
have them withdraw the suit.

But please note from the disclaimer below  - this is no legal or
professional advice, though I hope someone with professional
experience can give you a clear answer.

Regards, Myoarin