Pravit,
I'm older than you-- I started Russian in 1958 with (probably) the same book, but it was by Stillman and Harkins then.

But for now, if y'all want a thorough grammar, with the nitty gritty about Russian - this is not for the faint of heart - look at Terrence Wade, A Comprehensive Russian Grammar. At least look at it in the library before you send in the money for it. It's got the stuff in it that you have questions about in your third or fourth year, or even more. When to use на, when в -- ехал в город, ходили на стадион, second locative? о лесе -- в лесу.