Thanks PietaS175.
Since I never got a response to this post, I went ahead and figured it out myself. I would up needing to search 6 different fields in the same feature class for the same value and this was simply to keep me from having to add the Query Tool 6 different times to the same app, one for each field and then users having to try each one until a match was found. I just hardcoded the Where clause and it worked great. The hardest part was finding and changing the namespace to prevent conflicts with the other Query Tool. The Query Tool did everything I wanted except let me search multiple fields for only one value entered in a single field, so I didn't think it was worth trying to write my own tool. I'm torn about trying to learn the Silverlight environment when I see almost no activity in the forum or the blog about it and no new stuff from ESRI. I'm just using the Viewer for Silverlight so that I can make some apps without writing much code.
Again, Thanks for your reply.
Steve