Hi,
You do not mention the size of your tank, but my first plants were a mixed collection from James Starr on ebay which contained a good mix of plants for £10 +p&p. He has various mixes so you can chose what you like.
Apart from the grow pot this is what I received, temporarily put in little pots with qravel to hold them down before planting in my 40cm cube.
If you look in P@H they usually have the Topica Heteranthera Zosterifolia 1-2- Grow Pots which you might have missed, though seemingly seedlings they do grow very fast.
Just carefully check the underside of the pot is not too black, indicating its old stock thats starting to rot around the roots.
http://www.petsathome.com/shop/en/pets/fish/fish/live-plants-and-aquascaping/tropica-heteranthera-zosterifolia-1-2-grow!-aquarium-plant
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