If you've got the patience to maybe wait a bit, keep checking the 'Swap n Shop' board on this forum. You can get all sorts of nice packages from members on here, and probably cheaper than stores.
But if you want particular things and you want it now, that website is a good one. Also there's a place called Sweet Aquatics (Don't remember their site, but you can search for them) that I have dealt with before, they are very good. Also check out aquabid.com for good deals on plant packages. Good luck finding your plants!
What plants are you looking for? A couple of times I have put together a plant package with several plants that I have and if you know what you are looking for I could do that for you or go on SNS and post a WTB (Want To Buy) thread and people will hook you up with plants. You will get great quality plants from SNS.