“So any ideas as its a new idea I am going into and want to get it right 1st time...”
It's great to lean from the mistakes of others and listen to advice. But one thing I can guarantee is that you won't get it right first time 
Successful email campaigns evolve, sometimes over years. Change a line, response rate drops off, change a subject line, your open rate increases 20%.
There are so many variables that there isn't a one hat fits all approach. It depends on what you are trying to achieve and expectations.
What you won't get is a flood of new customers from a cold sales mail. So normally the aim is to introduce yourself and try and generate a potential lead. The hook on the mail will send them to a landing page which will make them want to get in touch. So the landing page has to be incredible otherwise your wasting time and money.
I would concentrate on getting your landing page/site up to scratch first, so any new possible lead has the highest possible chance of converting.
Then decide on the mail message, short to the point. Then one of the hardest things, convincing someone to actually open your mail and not delete it, so a killer subject line.
As I've said before, when it comes to data, it's about quality. So you want highly targeted data, tailored to match your ideal client base. No point sending to a fish and chip shop, or someone like us who aren't interested in import/export.
Email campaigns are an art form, and big companies will normally have a dedicated marketing person or team to develop and manage them. So for most of us, we tend to learn the old fashioned way which is trial and error 
Sending snail mail can be a very effective way of doing things, but the cost obviously goes up as you have postage, mail merging, printing etc. Or another option, telesales, get a call centre to try out some lead generation. All depends on aims and budget.
Be interesting to hear some other thoughts on mail marketing.