From second-hand experience (family and friends) I think it's fairly straight forward to get a tourist visa (obviously dependent on your nationality). The two common confusions are the 'invitation' and the entry/exit dates. You need an invitation letter from a Russian business/individual/accommodation provider etc. to apply. Secondly you need to plan your trip and entry/exit dates prior to applying.
This article gives a pretty solid summary of the visa process, albeit written for Australians specifically:
Some things might change depending on your passport. Hope that helps! almost 3 years ago