I am creating a search sub that needs to SELECT from several tables that match the search criteria. The problem is, I don't know how I should go about SELECTing records simultaneously from several child tables.
Very simple. If you've created the relationships right (1:m), define a new query in design view and add all of the tables. They will automatically show the relationship you've defined.
Choose your fields from the different tables - ie, "drag and drop" from the tables into the design grid. Finally, write your criteria against the particular field in the grid (every field will have a criteria; so, if you want the criteria to say, for example, "Europe" in a field called Region, type =Europe against Criteria under the field Region).