The price of a college education, which hard-pressed parents have long said is going through the roof, has done just that - only there is apparently no longer a roof. As Gertrude Stein said, ''When you get there, there is no there there.''

For 1981-82 undergraduates, tuition charges alone are crashing through the $7,000 barrier for the first time. Total fees, including room and board, are not only shooting past $10,000, but also emerging strong on the other side at such pace-setting schools as Harvard, Yale, Brown, Bennington, Columbia, the Massachusetts Institute of Technology and Stanford.

At several campuses, they carry such canny price tags as Princeton's $9,994. Outstripping the inflation rate by several points, the increases will commonly be 15 percent and often more. A benchmark 20 percent rise has been announced by Boston's Northeastern University for four of its colleges, where freshmen will pay $4,500 tuition, with a 16.7 percent rise to $4,200 at the other colleges. Cornell's endowed colleges will go up 18 percent to $7,000 tuition, with housing and dining increases expected to bring the total to $9,864. Student Aid a Concern

The increases come at a time of severe concern over the Reagan Administration's announced goal of limiting Federal financial aid to students, and many schools are increasing their own budgets for student aid. ''I have never been so beside myself about financial aid, both at Barnard and across the country,'' said Suzanne Guard, the Barnard director of financial aid.