Thanks for clarifying. I was referring to getting an invitation from a travel agency, who will make a token "reservation" if you are getting only visa support from them. If you arrange it through a hotel, they're going to want you to stay with them.

All visitors to Russia must have an invitation. For private stay visas, this is applied for by the inviting party with the local Russian authorities. For a tourist visa, this is issued by a travel agency or hotel. There are a number of agencies that will issue an invitation for around $30. You can then make your own arangements for lodging.

You can use a tourist visa even if you are not staying at a hotel, but check with the agency that issued the invitation about how to register the visa.

WayToRussia.net has a nice visa guide.