I haven't filled out a tax

return for the last 14 years and
(A) I owe them money from 1990
or
(B) they owe me money since 1990.
Can I get the money owed as it's over 10 years and do I have to pay them they money owed?
I should be a nett receiver of money over the years.

I presume that you're PAYE and not self employed or something like that? If you are PAYE then there is no onus on you to file income tax annual returns unless not doing so would result in your affairs getting out of date. Ultimately it's the individual's responsibility to ensure that his/her tax affairs are kept up to date. In many cases the processing of p45s, P60s, tax credits etc. by employers result in things being kept up to date correctly. However I personally would urge everybody to check their records (payslips, P60s, statements of tax credits etc.) to ensure that there are no discrepancies on an annual or more regular basis.

I seem to recall that there may have been some time limit on how far back tax can be reclaimed but I can't find anything authoritative on this. If you owed tax then I don't think that there is any time limit and you need to check of any penalties or interest may apply.

Yep PAYE.
Ideally I want to know if I owe them back tax from 1992, can I offset that against rebate owed from 1991?
I think it's 10 years which is changing to 4 from Dec 04.

I want to know if I owe them back tax from 1992, can I offset that against rebate owed from 1991?

Chances are that interest and penalties may apply to the outstanding liability which may cause the full amount to exceed any outstanding excess paid. However I presume that you can offset an unclaimed overpayment against any outstanding liability (possibly plus interest and penalties). I've always found the Revenue quite reasonable/pragmatic in dealing with such issues even when they involve outstanding liabilities so you might be as well contacting them. If you need to do so in confidence first then you could always send them an email.

I filled in a end of year return about 3 years ago simply because I thought I'd overpaid. Turns out I hadn't, but instead owed revenue €1500 approx. They proceeded to deduct just €15 per week from wages until the debt was paid, which I think was quite reasonable.

According to Colm Rapple, you can go back 6 years.

However Revenue can go back as far as the like when assessing an individual. Seems a bit unfair!

You can claim back for 10 years but this is being reduced to 4 years effective 31st Dec 04 deffo medical but not sure about anything else.

Where do I get a one of these forms to fill out. I want to make sure my tax is in order. Also I think I am probably owed some Rent Allowances for two years. Would I claim for this on the same form?

Is there a list of things one can claim for anywhere (for all professions, I hear some professions such as nurses and teachers can claims for different things)

Where do I get a one of these forms to fill out

What form? If you mean a [broken link removed] or some other standard return form then you will get these on the [broken link removed].

Also I think I am probably owed some Rent Allowances for two years. Would I claim for this on the same form?

[broken link removed].

Is there a list of things one can claim for anywhere (for all professions, I hear some professions such as nurses and teachers can claims for different things)

Tommy McGibney has a handy summary of these on [broken link removed].