Most conflict checking applications exist as a module integrated within law office management, accounting, or case/practice management software in order to enhance the total automation of your law office and to avoid duplicative entries.

Here's one stand-alone product that does not require tremendous resources:

• Conflict Checker: Offers free Demo that can be downloaded from the website and free e-mail technical support. Uses very little disc space and claims to do very quick searches. Very moderately priced for networked version with unlimited users.