I've only seen one group mix Breakin', Poppin' and Lockin' well. That group is Captain Crunch and the Funky bunch. (if you know any others, let me know.) I've only seen a couple videos of theirs, but both impressed me very much.
In this video they do mostly locking
http://www.youtube.com/watch?v=SFvhuo4etXE
The other video was from the lockers summit '84 and they won the 3v3 competition. In that video they did mostly poppin' and some tougher breakin' (windmills, it was '84 after all).
http://www.lockerlegends.com/default.aspx?p=115722
It happens time and time again; I'll find some dude, from some crew, and from the get-go I ask if anyone in their crew locks. The answer is usually "Yes.", and the person who locks, half the time doesn't, and the other half, do a small roll and a sloppy point (I'm guilty of sloppy points, I know better) and claim that locking is either 'nothing' or 'not impressive'. It seems that locking is an aquired taste. Rather, the biggest problem here is that Portland has one good locker (my teacher)!
I kinda' like where locking is now. Among the hip-hop culture, it is a rare novelty, and among the masses it is obscure. Locking isn't on Gap commercials and 'So you think you can Dance?'. Strangley, I love watching youtube videos of beginners like myself. Because of the overewhelming positive attitude of locking, there is no tolerance for agressivle promoting oneself. I have many harsh, crude, and negative opinions about many things, but honestly, locking is helping me see better things in people.
Thanks to the internet, there is enough information and resources, however, as Wavedash pointed out, if you want to gain that next level, you must be taught in person. Wavedash is fortunate to live in so-cal where locking is strong, and I am dang lucky to live in the same pizza delivery area as a great teacher. But I can easily see myself (in a couple years) buying a ticket to so-cal to take a class.
I'll be gone for a couple years in about a week, when I post a video then, hopefully, I'll be much more crisp. I have a few exercises to promote cleanliness, and after a couple years of soley polishing what I know, I hope I'll be pretty good.
Let me ask what do
you think of locking, and what has it done for you?