Two day HALF PRICE sale & advice needed

Three things --

1) All 8x10 prints are on sale for $5 each (normally $10) from now through Friday. Just go to my shop, add what you want to your cart, write "HALF PRICE" in the message to seller and wait for a revised paypal invoice. OR e-mail me at kategabrielleart@yahoo.com with what you want and I'll invoice you (Personally I prefer this option since etsy fees are KILLING me lately..)

2) When it comes to business matters I am totally 100% incompetent... I have some blog ads but based on my google analytics and sales I don't think they work. I tweet and have a facebook page, but I really can't think of anything else? How do you promote your work when you're inept at business, and practically broke? Suggestions are very very welcome!

3) I e-mail customers to thank them for their orders, and give them a shipping time frame. Do you think it would be a good idea to also ask how they found my shop and offer some kind of incentive if they tell me (like maybe a free mini print?) I really need to know where customers are coming from and etsy doesn't offer any kind of checkout tracking.