The best time to plant berry plants is when they are still dormant in early spring (March & April). Most nurseries keep them (up to as late as June or so) in refrigerated storage at about 28ºF until they ship them to you.
Good nurseries grow plants under strict guidelines to minimize soil fungus problems/insect transmitted viruses and have much more flexibility with respect to spray schedules since they are not planning to harvest any fruit. Any plants I would give you ( or you would get from a friend ) would have all the various problems that existed in the location where they were grown. Growing high quality fruit is hard enough as it is --- start with the very best nursery stock you can get !
Some of the high quality mail order Nurseries I would recommend that have a good selection of Strawberry, raspberry, and blackberry plants, deal in smaller quantities of plants and accept credit card orders are:
Nourse Farms, 41 River road, S. Deerfield, Mass, 01373
Indiana Berry & Plant Co.
2811 U.S. Hwy. 31, Plymouth, IN 46563