Need to setup a crawler

We need to create a automated crawler that will log into a website, extract the required data. Extracted info should be stored automatically into mysql tables. crawler should get the user/pass from a config file, login into the website at regular intervals, crawl, extract, store the data at periodic intervals; Make sure that the account won't be banned. crawler script should be easily changable to repeat the same on different websites, if needed. Serious bidders only, Please bid only if you have done this before.