I just wanted to take a moment to give some words of encouragement to anyone who is thinking of taking the plunge into creating their own themes. It does take a significant amount of time at the begining, however once you get the hang of it, it takes less and less. I competed my very first theme on 4/5/09, so right around 3 months ago. Since then I have completed around 10 unique themes and around 30 variations of those originals.
I can't speak for all theme makers but for me and many others its addicting and really, really fun.
Here are the steps I took to get going:
1. Download Plazmic theme builder here: Plazmic Content Developer's Kit v4.7 for BlackBerry (its a pretty hefty file so it takes some time to download)
2. Your also going to need a image editing program. If your familiar with photoshop it works great. I use a fee program called gimp that you can get here Gimp.
3. I would recommend finding some basic icons by searching online. You can find many free ones just make sure the ones you use are open license. Keep in mind you can use your image editor to make you own as well.
4. I started by making a basic Zen theme to get use to the functions of plazmic. This helped me a lot to get use to the lay out etc.
5. From there move into the custom option. There you have many more options to play around with.
6. Don't get frustrated. There are areas that if its not done right, it may not look as good as it could (i.e. Icon size)
7. Ask questions, there is no need to re invent the wheel. Feel free to PM me or post any questions you have. Myself and many others are here to pitch in and help.
8. Move into creating animations and SVG files. This is a bit more advanced and where you create docks and animations.
I hope this gives a few people that were hesitant to start theme building to finally say "yes I will do it!"
Let's see your creativity and Enjoy!