Links help your popularity with search engines. They should also bring you more visitors, if sites that link to you are relevant, and have high traffic themselves.The key word here is "relevant". Link farms and fr'ee-for- all link sites will probably reduce your ranking and visitor popularity if anything. After all, if you visit a fishing site, you probably won't be interested in links to baby food recipes, car maintenance, or knitting. That's view search engines take too - it's not quantity, it's quality that counts.
Visitors from those links won't be buying much either. People prefer to buy from specialists or experts, rather than a jack-of-all-trades.
So what's a good link?
Take a good look round site. Is navigation easy? Is content useful, and relevant to your visitors? Are you happy to recommend it to them?
If answer to those questions is "Yes", then delve further. If you're selling a product or service, will they be in direct competition? If so, you won't want to link to them. Check site with IE Google toolbar (a fr'ee download from http:/ oolbar.google.com ) and see how high it ranks with Google. If it's same as, or higher than, your own site, then it's worth considering for a link.
Is link page easy to find? It's no good having a link on a high-ranked site, if their visitors never see it. Ideally, they should link to it from every page of their site, and link should be part of main navigation - not down at bottom of page in "small print".
So how to find those links?
Some you'll come across yourself, while surfing, if your website is related to an interest that you have. I've even found good links when helping my children with their homework! Keep a "jotter" program available while you surf, so that you can make a record of these sites. Or use a real jotter if you prefer!
But tool I use most, and which has made finding and maintaining my link pages much easier, is Arelis - Axandra's Reciprocal Links Solution, http://www.firstwebbuilder.co.uk/info/arelis.html
You can search for links by keyword, by using a website that has a similar topic, or by checking for sites that aready link back to you.
Once you've deleted any sites that you aren't interested in, you can then use built-in browser to visit sites and decide if they should be included in your links directory.
Arelis stores these in a database. You can email webmaster (Arelis will search out email addresses while it finds possible link sites.) You can categorise sites however it suits you. You also have a host of options on how far your reciprocal link with each site has got, from "Not contacted yet" to "Links back", with a range of other options to cover all eventualities.