To be certain, you should:
* Consult your owner's manual: This is the best source of information specific to your vehicle. It will have diagrams and precise instructions.
* Look for a cylindrical canister: The oil filter is usually a fairly large, cylindrical canister.
* Use a flashlight: It can be difficult to see under the hood, especially in low light.
If you're still having trouble locating it, a quick online search for "1993 Chevy S10 Blazer oil filter location [your engine size]" with images should help. You'll find plenty of photos showing its precise location on various S10 Blazer engines.