The most accurate information will likely be from STR (aka Smith Travel Research). STR gets real data (rates, occupancy) from hotels and aggregates it. Their STAR (Smith Travel Accommodations Report) allows participating hotels to compare their actual data against the aggregated data within a competitive set of nearby hotels. While the STAR report is only for participants hotels, STR has other products. Unfortunately, none of them are free. Some relevant reports seem to be in the $500-750 range.

STR: http://www.str.com/about

If you're looking for free data, you might try the convention and visitors bureaus of US metropolitan areas. It's likely that they will have general information that meets your needs.

For example, here are reports from the Las Vegas Convention and Visitors Authority: http://www.lvcva.com/stats-and-facts...or-statistics/