There's probably a gazillion brands all about the same. Just make sure it has a tip-over protection switch.. that shuts it off if the heater falls over. Mine also has a thermostat and multiple fan speeds.
I bought the one I use at Wal-Mart for about 20 bucks, works fine. But as a hint, you better hurry if you wish to purchase one, these fall
into the "seasonal merchandise" category and will be replaced with "summer fans" on the shelves... real soon.