www.rscemulation.net, or www.rscangel.org, 2 good sites, rscangel is an old server that is being redone by pompano and updated.. and rscemulation is the server with the most active player base, but their all assholes and a few corrupt moderators.
www.rscreloaded.net, is one of the best servers, its a custom server, but the admin is in active, and so are the mods, but the server is awesome otherwise.
In order to have RSC access you must have logged in between 4 August 2005 and 15 January 2006 or one of the past re-openings. If you haven't then your S.O.L. and you will need to buy a cheap acc with RSC access. Another good place to look for an account would be http://aposbot.com it seems to be the most "active" rsc forum atm. It shouldn't be too hard to find a cheap account since anyone that was a member last year most likely signed in for a couple minutes to get the classic cape.
Try playing the game on one of the aforementioned private servers. If you enjoy it, then I'd recommend purchasing an account that has access from someone here on Sythe. It is quite a different game though.