ignore case in where clause

I am currently using lower(column) = '' for matching case insensitive. I
know that there are ways to do this with regular expressions too. I recently
noticed that including even one lower causes severe performance issues (from
290ms to over 80Kms).

What is the best way, performance wise, to do case insensitive matching? I
could spend a few hours testing if I have to, but I'm hoping someone knows
off the top of their heads.

Using 8.3 currently. I am a programmer, not a database person; but we don't
really have a DB here, so I do what I can.

Thanks.

Edward W. Rouse
Comsquared System, Inc.
770-734-5301