[@cuttlefisk]
First I must say this, as I find it important to use and it's helpful and convenient in my opinion. The bottom right of each post in a thread there are two buttons a Quote button and an @mention button. Use the mention button to cleanly tag the person so they receive a notification about the post. 

All I can really say about rping here is you should just look at the interest checks of whatever sub-forum you feel would be most comfortable for you and look to see what you'd like and tell them that you are interested and/or whatever they say to do on the post.