Most of the sites are marketing ones that people have to pay for. Is there somewhere else I can get the stats on?

i dont kno about that but if you want to date thru the internet i suggest that u try "Match.com"

There are a few tools that exist using which you can get the volume of search being made using various keywords. This search volume would be indicative of the number of people using the service. www.searchenginerankings.com.au provides this service. Other methods to acquire this are IBIS WORLD. If you just google it, you can find it. They have reports on almost every industry. If you want still more indepth research, you can commission a market research firm..

If you want in-depth information, you're probably going to have to pay for it. It's not clear exactly the sort of analytics that you're after, but you could try Hitwise who would probably have an internet dating category.