This document outlines 20 free and low-cost web tools and services that libraries can use to enhance their digital services and programs with limited budgets. It provides descriptions and instructions for using tools for websites, images, ebooks, surveys, open-source integrated library systems, translation, tagging, reference, user support, online book clubs, web analytics, social media, forms, online classes, maps, audio, video, and more. The document aims to equip libraries with options for building "library 3.0 services" without large budgets.