First, those pots are too small for growing bamboo over the long term. Second, to my knowledge, seeds are not currently available for those two kinds of bamboo; in fact, bamboo only put out seeds every 20-150 years, so your likelihood of finding seeds available for a specific species are slim. Third, there are seeds available for some species, but you should only buy from U.S. sources as it is a violation of Federal regulations to import any kind of bamboo seeds without a one year quarantine. Fourth, if you succeed in growing bamboo from seed -- and it is not always easy to do so -- it will typically take about 5 years for a plant to reach 4-5 feet...and indoors it will probably still be much smaller. So, if you really want to grow bamboo, you should go to a nursery that specializes in bamboo and buy yourself some potted bamboo divisions. These are plants that are made by dividing bigger bamboo and re-potting them, and is how most of us acquire different species. I'm not trying to discourage you...just injecting some real world considerations. Good luck.

If you get seeds off ebay, you should probably make sure the seller guarantees you a decent germination rates because I've heard of many buyers who have had 0 germinate. Also make sure you get a clumper for indoor growth. I think ventricosa might work, but to be sustainable, you still need to put them outside in the summer to get full sun. I would suggest starting them in a paper towel, then transferring them to a seed-rack, but as kudzu already stated, it will take a while to see decent results so you might as well get the ones that upsize fast.

Here's how a clumper grows in a 15 gallon pot 2 months ago, and this was a 5 gallon pot of d sinicus purchased at tropicalbamboos during winter of 08/09. This picture shows it putting up its 4th culm.

Here is a link that might be useful: dendrocalamus sinicus

Thanks for the info steve. I had been looking at seeds on ebay.