Articulating an idea is key in selling. In fact, it is not just about conveying an idea, it is about influencing others and being a change agent. As a small business owner, are you up to that task?
If not, there are several organizations out there to support you and help you grow professionally.
Toastmasters Int'l: These folks have meetings all over the world, and in your own community probably there are a multitude of choices for weekly meeting times and locations. Check them out, and go their to increase your presentation and leadership skills. It does not cost much to attend, and everyone is welcome, no matter your level of comfort in speaking. Visit as a guest, and see if you like it. Try another group if you don't, before you write off this route.
National Speakers Association: This is a great organization if you have a higher comfort level in front of a group and plan to do more professional speaking. I enjoy that there are a few brilliant, well paid public speakers at most monthly meetings - NSA is in the U.S. and there is an International group as well.
Dale Carnegie: I haven't been for five years, but I attended the Dale Carnegie general course and the the sales program. After that I worked as a graduate assistant for both programs, and have seen people change their life through one of these programs. Definately worth checking out.
Local community colleges and adult ed programs: There are usually speaking and presenting courses at nominal fees.
Once you get your skills polished, then do role plays. Be the customer, and have one of your counterparts or colleagues sell your product or service (or their product or service) - then switch. If you did this 100 times it would not be too much. Find ways to incorporate role playing into sales or operations meetings - or if you are a micro business, get together with peers on a regular basis and work on this one skill. It could have great results for you.
I agreed many years ago with the thought that success is a journey, not a destination. We don't know it all, and just ONE tweak to what you are saying in your presentation could mean the difference between getting the sale instead of not getting it. With that in mind, how could one not invest in themselves?