If you don't locate what you're looking for trying Insweb, use another online service such as esurance.  Esurance not only gives a comparison of Iowa car insurance rates, but it also gives a wealth of information about buying car insurance.  If you still aren't gratified, the next step is to pick up the telephone and call popular insurance companies.  Most states such as Iowa have representatives from the major insurance companies, like State Farm and Allstate.  You can also try national carriers like Geico.