I found several by putting in te common name on daves garden then it showed me pics in others gardens then a list of vendors who had some. One place did not have that much feedback but no neg. Here is their site. I like that plant also might have to do more study on them.
Gardensoyvey.com
Jill

Linda,
You can trade on the Plant Exchange or the Seed Exchange.

You can try this site http://www.gpc.edu/~decbt/sales08spring.html Its the georgia native plant botanical gardens. Ive bought spigelea there before. They have sales alot so maybe they wouldnt mind selling you some via mail.

Hi doucanoe....
How many do you need? Want?
Here's a TC lab in Fla. that sells liners in trays(flats) of 72 count. Their current availibility indicates some scheduled in May.
I have seen these at Nurserymen Association shows and they are large sized, healthy looking plants. At 95¢ per(+S&H), they would be a bargain, But only if you can use that many.
Rb

Here is a link that might be useful: Agristarts 3

razorback33 ,Agristarts 3 looked them up and they only sell to wholesellers.

Jill....
They have never asked me for proof that I am a wholesaler/retailer. I am neither. I just use a nursery name that I made up on the spur of the moment. No loss. if you try and fail, but if you don't try, then you can never know for sure! I purchase plants wholesale, from many TC labs across the entire US and have for many years. You just have to meet the minimum order requirement, whether number of plants or dollar amount.
Rb

i have ordered from the nursery linked below and have been pleased with the plants she sends.
the price is $7.00 + s&h.

Here is a link that might be useful: mail order natives

Thanks, everyone! I don't need 72 and since I am taking a chance they will tolerate zone 4 I don't want to invest quite that much! LOL

Jeff, since you have been pleased, I think I'll order a couple from the site you linked. Thanks a ton!

Linda

Here's another source for Spigelia marilandica (potted plants). $5 +S&H, which is about what our local Botanical Garden charges for them at plant sales.
You may have problems growing this in Zone 4, unless you have a microclimate area that doesn't fall below -20°F. Heavy mulching after the ground freezes and winter snow cover could also be helpful.
Check comments at Dave's GardenWatchDog for any online/mailorder company before placing an order!

Here is a link that might be useful: Easy Wildflowers