they have a whole collection that cover pretty much all aspects of salsa on1.
Their videos, are quite informative, and generally good, Al has a funny streak to him, which gets cumbersome when you have to rewind.
For your friend I would say go with their beginners level that will keep him/her busy for at least a month ( it has footwork, basics, partnerwork). For you, Eddie's styling.
Alex Da Silva also has some videos however I have yet to see his beginners one, his intermedium is ok interesting combos but not much detail in the execution of the moves.
There is styling video by Olivia Dasso, (oliviadasso.com) however for detailed instruction I think Eddie's one may fit better.
There are several videos out here , and hopefully this post will bring some other recommendations, in general having recommendations from fellow dancers is good when buying a $30 - $40 dvd as some of them can be terrible
For On1 CBL-style, Mario (millionmovesman.com) and Leon Rose (available from steps4salsa.com) have good beginner - intermediate - advanced DVDs. It's mostly moves and routines, not so much styling - but they break the moves and routines down very well, show from different angles, give handy "execution tips", etc - you can actually learn it from their DVDs. steps4salsa.com has a ton of stuff and deliver quickly even to my neck of the woods.
That's a pretty big range, M. And I like the suggestions the others have been giving. If your friend can handle advanced stuff, then it's quite possible that they'll be able to digest On2 videos and translate it over to On1.
Is $$ an issue? IMHO, you'd be better off taking privates from one of the ladies in Salsa Salvaje, all of whom have very nice styling, and I don't think that they're all that expensive from what I remember hearing.
John Narvaez and Liz Rojas from San Francisco have an excellent instructional series. Their beginner and intermediate videos are On1 but their advanced and ladies' styling videos are both On1 and On2. Their web site is www.salsamania.org. Unfortunately they don't sell the DVDs online so you may have to find them at a congress.
Shaka Brown's videos are very good if you are only interested in On2. His site is www.imambo.tv.
For older On1 videos, I like Josie Neglia's series. Her ladies' styling video is the best breakdown of the basic step I've ever seen. She goes into detail on what you should do with every body part, from foot position to holding your head high. You can find her at www.latindance.com.