For a $500 budget (+-100), what to get depends a lot on what you need and what you shoot.
My recommendations:
For light traveller tripod:
Sirui T-2204X matched with
Markins Q3T
For Macro work:
Vanguard Alta Pro 263AT matched with
Markins Q10
For landscape tripod:
Manfrotto 055xprob with
Markins Q10
If want to spend a bit less money, then replace the Markins heads with a similar one from
Photoclam. Or save even more, get manfrotto heads or Sirui G20 heads. Remember the strongest your tripod can be, is equal to, the weakest part of your entire tripod setup. So no point buying a super strong gitzo, and match it with a cheap sirui G10 ball head.
On top of the tripods, I strongly you get an
L-plate. If you decide to go for manfrotto heads which I use, it is kind of rare but you can get it from Camdapter. See it
here.
And becareful of max weight ratings. Different companies state it differently. Some are very optimistically aggressive, while some are very conservative. You have to figure out how to spot who is which. Best is to go down to the store test it out. put weight on the top of the tripod by pressing down with one hand. And using another hand with 2 fingers, strike the tripod legs. See how the vibrations feel in your hand that is pressing down on the top of the tripod.
If you ask me what I am using? I am using all aluminium tripods. 190xprob+488rc2 is my main setup. When I travel, I use Sirui T-1004x+494rc2. The 2 setups combined cost me slightly less than $500. But then again, I do not have a 70-200/2.8 or 80-200/2.8. My heaviest lens is around 600g