Have you checked with your local community college? In VA, those are the only places that seem to have Admin study tracks. And many offer online programs. There are also schools like Bryant & Stratton and ITT but I'd steer clear of them simply because if you choose to pursue a Bachelor's later on, their credits usually don't transfer (ITT even advertises that fact in their commercials if you read the blurbs as they come up). And they also cost quite a bit more than a community college.
I attended a secretarial school back in the mid-80's and earned a Diploma as a Legal Secretary. Over the years, that diploma has come to mean less and less to prospective employers because so many want to see "Associate Degree in X" or Bachelor's or Masters to do what I've been doing for 20 years. Very frustrating to say to least especially considering that they don't want to pay squat for those degrees and I have made a point to keep up and self teach myself new programs and technologies as they came along or were needed. And that school I attended had a great reputation among the larger local businesses for turning out highly qualified secretaries. They closed last year for some reason or another amid a bit of controversy.
I've toyed with removing them from my resume for that fact alone. I don't want to be associated with a school that now has a bad rep instead of the stellar rep it had 20 years ago. I have some college courses under my belt but never gave up on pursuing a full degree because I got tired of hearing how much I was overextending myself and the questions of why I was doing it. I know I should for myself, but some encouragement from family and friends can go a long way and I'm the type that needs it.