As long as you have the winter ahead and there's no snow on the ground, you should still be able to plant garlic and get full sized bulbs. I've started planting as early as mid september, up until december with all different species.

You can normally get soft neck garlics at the grocery store, but if you are interested in larger cloves, you can probably get a good deal on eBay with hard necks. Unless you are a collector, I would suggest getting cloves because they will give you immediate results next spring as opposed to an extra season or 2 depending on the size of the bulbils.

I think all of them will produce flower heads, and you can plant garlic pretty much anywhere that gets enough sun.

It is not too late, but it's definitely time. Your problem will be finding "seed garlic". Most all of the traditional vendors are sold out now. However, here in the south, the best types of garlic for us to grow are the soft neck varieties (good storage kinds), and these are what you normally buy at the grocery store, as steven said. You want your soil to be well drained, fertile (I added some Blood Meal to mine), and consistently moist. You will also want to mulch to keep down weeds.
Buy the biggest heads at the store you can find, break them apart and plant the biggest cloves. They will come up in two or three weeks with nice green tops. The bulbs will be ready for digging in late spring or early summer.

Here is a link that might be useful: Grow Your Own Garlic

Here is a site with lots of info about growing garlic and special considerations for growing them in Texas. I bought my garlic from this site and thus far, I can tell you that all have sprouted and looks strong.

http://gourmetgarlicgardens.com/growsouth.htm

According to their site, in the South you want to plant softnecks (as stated by others). They recommend planting around the fall equinox (end of September) so that the garlic gets a good head start on spring...good root growth before winter so that when spring arrives, it is ready to bulb up. The reason for this is because in Texas, our 'springs' are fairly short - in that - it gets hot early. So you want the garlic in 'ready to bulb' shape as soon as the temps turn warm. This is from my research as this is only my first year growing it myself.

With that being said, I think you may still get a successful crop if you plant NOW. Maybe the bulbs won't get as big. And we could always have a cool spring (who knows in Texas).

Here is a link that might be useful: Gourmet Garlic Gardens

Nice link, says just about everything I would have said. I grew garlic in San Diego for several years, wish I'd had such a reference then.

I'll only add:
"Question 2: I want the flowering kind. Where can I find it?"

Do you mean true flowers, or the flower-like stalk (scape) that forms on hardneck garlics? While some hardneck garlics may form flowers mixed in with the bulb clusters on the end of the stalk, the only "garlic" that flowers is Elephant Garlic (which despite its name, is actually a bulbing leek).

This is the first year for me too.
I planted in October.
I have Dushanbe,Chinese Red & White, Italian Loiacona & a bonus Greek garlic.
I got mine from wegrowgarlic.com.
They have good description of all their garlic.
Karen & Mike were very helpful.

Here is a link that might be useful: garlic