Based on my short experience with Google adwords in Japan, I think the following is a good strategy for newbie adword users.
1) get great ad copy and landing pages 2) sign up for adwords, but don't syndicate yet 3) test your ads and landing page using google 4) redesign! & test more! (Add negative keywords etc..) Once you have achieved a fair CTR on google (at least 1.5%) and a satisfactory conversion rate on your landing page, then 5) syndicate
I found that an ad with a google CTR of 1.5% gets a syndicated CTR of at least 2% as well as higher conversion rates. Syndicated ads in Japan provide about 3X as many impressions as Google alone (for my keywords)
I think this method gives both the advertiser and Google the highest possible returns.
Good suggestions David - especially putting spotlight on the ad copy testing part.
However, I suggest that all AdWords users syndicate their ads right from the beginning. That's because this helps you decide on the best ad copy very quickly since you will be collecting more impressions per day. You can quickly get rid of or fine tune your non-performing keywords.