Besides here sometimes you can find a buddy on bonairetalk.com. It's actually not a bad idea to dive some of the north resorts either. Sand Dollar condos is on Bari Reef - one of the better shore dives for fishlife and Dive Friends has a shop there. Their entry is down a few steps from the tank storage onto a beach.
Lots of the other resorts have dive docks also. Here's some of them:
Den Laman also on Bari - Bonaire DIve & Adventure. Smaller property so less likely. Don't use their dock unless you're a paying guest...lol.
Buddy Dive next door to Sand Dollar - highly likely to find a buddy there. Especially in the bar.
Habitat next to them - both the LaMachaca (small) wreck and the south end of the Cliff divesite are accessible from their dock.
If you happen to be staying/using Dive Friends at Hamlet Oasis, just getting in there to do your BMP dive is a pretty good exercise in how to safely access the water - there's no dock there and it's a rocky entry.
At many sites past divers have indicated the best entry - it's not always right where you park (south side) either. Often coral rubble is piled up un-naturally. At some sites look for sand channels out to deeper water also - this is one of the most illustrative but it's the
Vista Blue dive site on the south end and currents there can be tricky. Don't do it until later in the week with a buddy or a guide. We swam 10mins. "north" but actually stayed just about even with our truck so got out and went somewhere else.
We actually made plans with 2 different groups waiting for our last flight to Bonaire. And then 2 other groups on our boat. One we saw a couple times leaving a site we were entering but we didn't make an effort to join any of them. There's not a whole lot else to do there so most people at the resorts, restaurants, bars tend to be divers or with one.
Also the standard dive vehicle is a 4 dr. small truck so most people have room for one more.
If you see references to BDSME - often called the Porter book - it's available on-island or here:
Bonaire Shore Diving Made Easy, BSDME, Author Susan Porter