Does google adwords work ? I've never used it but I heard that alot of competitors click on your advertisment to make you lost cash ?
Theoretically this is possible. But in practice, it won't happen very often. For one thing, you need to be in a highly competitive niche. Forum members have certainly reported this happening--yes. But I wouldn't worry about it for now, esp. if you're a new advertiser.
Google adwords does bring you high targeted traffic but you need to set up your campaign correctly. In short, you must follow the Quality Score guideline, make the google think that your ad copy, keywords, ad group, and landing page is highly relevant to what their visitors are searching. Quality Score is very important in google, you can learn it through this forum or buy some adwords relating ebook to read. If you have prepare some ad budget, why not give yourself a try but you need to really fully prepare before let your campaign go live.
Set up you campaigns to the targeted location where you wanted to advertise...still if you feel that your campaigns are affected with fraud , you can always send a request to google for investigation for fraud clicks on your campaigns.