I'm going back to Bonaire this summer to dive the east (windward) side but I didn't think there was much shore diving on that side based on my research, no first hand knowledge yet. TONS of it on the leeward side... and great dives at that!
Yep, you can shore dive the east side but I do recommend a guide. Safer and you will get a lot more out of it.
http://www.scubaboard.com/forums/bonaire/455505-boca-spelonk.html
Richard has a thread too. Maybe he will link or I will try and find it...