Peak of swarm season runs middle of April to middle of May, this year it was a little early. I got about 20 calls this year but handed most of them off to other beekeepers. You just have to put your name out there on some of the municipal and pest company lists. I dont think the club does a hotline but I know that Jim Pickett has been a central figure in swarm collection and will often send others to collect swarms. Not sure about removals, I dont really want the headache, but I would certainly not do them for free. Beesource.com has some pretty good discussions on this. Overwintering is typically pretty good as our winters are mild. Varroa and the viruses they carry are way more of an issue IMO than starvation. The only way my colonies do well/overwinter is if I knock back varroa populations before most of the winter brood are produced, sometime in the late september to early october time-frame. For flow, a strong hive in April will do really well on blackberry, tulip poplar, locust, and others. The main flow is typically dutch clover which the bees really start paying attention to starting the middle of may and last through the middle of June. There is usually a pretty good dearth from July through September and then a fall goldenrod flow which cant be counted on but is always nice when it happens.