Where to now?

I've been programming for a few years now and consider myself a competent programmer. I'm particularly interested in game programming and engine design. During the time I've been teaching myself how to program I've come across several plateaus in my learning curve which I've eventually managed to cross. It seems like I'm at another one now. I just can't figure out how to implement more advanced algorithms such as BSP's, ROAM. I think I understand how BSP trees work, and it seems quite simple. I can't figure out how to actually implement any of this stuff because they are just so complicated. I've tried looking at other examples however I don't want to be cut and pasting from someone else. Does anyone have any tips where to go now? I think perhaps I could do with a good book, can anyone recommend any?

Thanks in advance.
Dave
Ps Has anyone noticed that Open GL tutorials always seem to be the strangest things? They are always simple stuff like how to make a polygon always face the screen or to add decals. Although there are some examples of more complicated stuff I cant find any tutorials.