hi. Id enter Coos Bay in the search field, theres been several similar posts like yours, and some of the threads have got some terrific information on them.
For 4yr olds, I know of 2 definate groups that are pretty popular. theres the gymnastics at the Boys and Girls club, they have several different days/times for 4yr old classes and the kids have a blast. Great way to meet up w/other parents of like aged kids.
Also, theres a dance company too over by Eastside. Also through the boys and girls club. They have a pretty solid group as well, I know some of the kids do both.
The libraries have story time and music time, just give em a holler and see what they have up. They also do different cool things like Reptial man comes, and other such venues.
I know personally of a few others who do homeschooling in this area. I know some have play groups together and w/the kids from the gym/dance program.
Anyhow, again, id search the forum for others wanting infor on family life here in CB/NB. theres some pretty good advice/ideas on some threads.
Good luck!