I think when vince says he's "brought in" he only means he has set up an account with these companies. No warehouse. He just places orders with the manufacturers as he receives them.
Some items I ship directly from the manufacturer while others are kept in the warehouse. It varies upon the manufacturer and a lot of times a quantity purchase is required on exercise equipment.
Weights for example I do have shipped directly from the manufacturer because of obvious shipping cost. However, items such as the Generic Pro-Spinner Bikes have to be sold in a quantity of 12 but they all come stacked on one pallet so FED-EX freight shipping for it is only around 200 bucks so its a really good deal because it amounts to about $18 dollars shipping per bike where shipping separately would be $60-$90 dollars.
Just a lesson for you folks in case you want to venture into selling equipment. Drop-shipping items for the most part doesn't pay because you have to charge a higher price for an item and most shopper will go with a lower price naturally