I just got a 96 corolla. The right wheel is making noises while driving so I took it to sears auto center for a check. The mechanic told me the strut has some problem and needs to be replaced. I think the strut might be deformed from a previous accident in which the car was hit in the right side by another car.
It would cost about 600 bux to get fixed.
Is it a must to replace both struts, or can I drive on without fixing it?

You can get away without getting it fixed, but that will cause other problems such as improper tire wear (more $$$ to replace quickly worn tires). The accident may have also caused other suspension damage not visible to the eye. It would be advisable to get both struts replace, but $600 is a ripoff if you ask me. Get a second or third opinion first. I would say the strut should be about $80 at most and should take about an hour to install at about $75/hr at the $tealer. $200 at most I would say, and that's a high estimation.

Thanks for your quick reply. Acutally I had a price quote from sears which includes not just struts, but other parts as well. I can't remember the exact name. It's something like strut mount. The parts would cost around 330 and labor costs about 300 including alignment.
Where should I get the job other than sears? I think sears has comparatively reasonable price when compared with other brand name garages.

I think you should try and find a couple independent Toyota mechanics and get some estimates, or you can ask various friends and family members for references for mechanics. If you still feel that Sears is the better bargain then go ahead and get the work done. What other work are you getting done other than the struts and strut mounts? Good luck with everything!

I just found the paperwork from sears.
The parts to be replaced
Strut 125 each x2
Mount KIt 55 eachx2

then installation for both $56x2+$55x2
Alignment is another $70.

so the total goes up to 600 after tax.

Labor costs a lot. I am still hesistating. Anyways I plan to sell the car after one year.

You can buy your parts online from places like trdparts4u.com, partznet.com, 1sttoyotaparts.com or toyotaworld.com and have them delivered to you and have someone install them for you. Buying parts online can save you big $$$ as compared to buying them from your local dealer, and you don't usually have to pay taxes on the internet.