I am assuming you mean 'garage' when you say 'pit stall'.
When you register on the DLB website, you will be asked if you want a garage for an additional $30.00
If you say 'yes', you then open a diagram of the 'Blue' or 'Yellow' garages.
I like the 'Blue' ones. They are open on both ends, so there is better airflow, and as such, are not as hot as the 'Yellow' ones.
The 'IT Crowd' is all over the place at Daytona. If you 'mouse-over' the garage diagram on DLB, it will tell you who is in the garages that are already reserved. Look for someone you know or a group of cars from you class.
There are currently no test days at Daytona. The track is extremely easy to drive and a whole lot of fun.
We have covered the whole, 'no test day' thing at Daytona on this forum before. The general consensus was in lieu of a test day, take your car to the dyno on the hottest day of the year. Get in your car and have the shop put a heater in the car with you. Then after 10 minutes, take out the heater and hose you with water for 5 minutes, then repeat for 30 minutes.
You are now ready to race at Daytona.