One wonders why Mr Collins did not seek a young lady in his own neighborhood, or among his own aquaintance:

...and though he belonged to one of the universities, he had merely kept the necessary terms, without forming at it any useful acquaintance. The subjection in which his father had brought him up had given him originally great humility of manner...

"Useful aquaintance" I take to mean a contact that might help in one's career, but IMO the gestalt of the paragraph also suggests Mr Collins was hardly at the center of the social scene at any time in his life. Although we are not given specific information, we would not be suprised to learn he had not previously met any eligible young women on his own; or if he had, he probably scared them off with his constant apologizing, his pomposity, or his poor dancing skills!