“I wanted to know, 20 years after the Stonewall riots, if gay pride and progress had finally begun to trickle down to the grass roots,” explains Neil Miller, a gay journalist from Boston, in his introduction to “In Search of Gay America.” So Miller spent a couple of years on the road, seeking out some of the more surprising pockets of gay life, and now he gives us a chatty and colorful account of his travels. In Search of Gay America: Women and Men in a Time of Change by Neil Miller (Atlantic Monthly Press: $18.95, 324 pages)