In my garden:

1. Yes.
2. Different types of Lilies come in turk cap shape. I have one turk cap Aisiatic, a few species and tiger that are turk caps. Here's the order of bloom in my garden, overlapping somewhat: Asiatic - longiforumasiatic- species - trumpet - oriental - orientpet - orange tigers - species. This year everything was out of sync. The asiatics & longiforum bloomed almost at the same time as well as the orientals & orientpets & species. Weird.
3. Trumpets, orientals, orientpets and many species are fragrant. I heard some new asiatics smell good, but I don't know which.
4. Yes.
5. Darker trumpets (Golden Splendor & African Queen) fare better in afternoon shade. Full sun bleaches them. The orientals are OK in fulll sun...could be because a lot of them are white or have white bands to reflect light. Orange tigers do well both in full sun & part shade. They grow the tallest in full sun.
6. Tigers carry virus, so say various sources. I had tigers in separate beds from my other Lilies for many years with no ill effect. This year, many of my Lilies fell victims to virus. The culprits were the newly planted lilies, not from the tigers.
7. My orange tigers face down, therefore turk caps.
8. 6"- 8"-10" depending on the types. Some species come in tiny bulbs.

Brilliant yellows I have are asiatics and trumpets. There are yellow orientals-longiforum/asiatics, but mine are not as brilliant as asiatics. same with orange.
Golden Stargazer & auratum are yellow and not asiatics. There are other yellow orientals & orientpets as well.
Orientpets are fragrant, the blossoms are large, the plants are very tall and bloom later than orientals, thus extending the blooming season.
Never tried van Bourgondien, but am tempted, because I had a very bad experience with B&B this spring, besides the bulbs were much smaller than before.

Tiger lily is a term that is very loosely applied -- i have even heard roadside day lilies called tiger lilies. I have seen pink tiger lilies!!! Well, that's what the label said, but....

Actually, tiger lily is a term that should really only be applied to Lilium tigrinum, whih is now correctly called L. lancifolium. (Sorry , I don't know how to do italics) Comes in yellow and orange.

In the same vein, turks cap should probably be applied to martagons, but is widely applied to any lily that has recurving petals.

Orienpets are expensive because they are a cross between orientals and trumpet lilies. These lilies do not hybridize in nature, - it's called a wide cross. Kinda like tigers and pussy cats. They're related, but they don't hybridize. It would be a wide cross. However, by the miracle of modern genetics, they are able to cross them in the test tube (lilies, not cats, though that thought is probably lurking in someone's mind. Rat killer par excellence.)

So, because it's genetic engineering, the cost initially was very high, and, I guess has stayed high. I suggest going to the North American Lily Society web site, and looking around. You should find a local society link there.

Some of the LA hybrid lilies are fragrant too. 'Donau' is an apricot colour and 'Fangio' is red, both have terrific fragrance. As far as a supplier, you can check out the Lily Nook's site. They list when each lily will bloom, so you can stagger bloom times better. I'm not sure on the shipping charges to the states, but all they do is hybridize and sell lilies. The bulbs are always top quality and they have hundreds to choose from.
Good luck and try not to get TOO addicted to lilies! ;)
Laurie

Here is a link that might be useful: Lily Nook

thank you.
that is an excellent site. I plan to do some fun-study!
Karen