Is there any university that provides I-20 for getting enrolled in GMAT , TOEFL or language course ? Will the I-20 provided suffice the F1 status requirement ?

When I had to wait for a semester to be accepted to college for masters, I joined Kaplan for GRE. Their I20 is vaild for F1 legal requirements. Although you may have to go to class every day during the weekday. They also require you to maintain log for certain hours studied besides class which needs to at Kaplan, kind of like studying in a library.