Tutorials

C++

Thinking In C++, Online Book by Bruce Eckel
ACM Introduction to C++
Basic Input & Output in C++
Online C++ Tutorial
C++ Reference Manual

SQL

Oracle SQL Reference

Visual Basic

Visual Basic Tutorials
Visual Basic Information Center
Visual Basic Bookmark - Online VB Directory
Visual Basic Internet Programming

Java

Sun's Java Tutorial
JavaTM 2 Platform, Standard Edition, v1.2.2 API Specification
JavaRanch Java Forums
Java Server Pages Tutorial
JARS.com: Java source code & resources

Perl

Core Perl Documentation
CPAN

HTML

HTML Tutorial - Beyond the Basics
HTML Tutorial - Web Tutorial
HTML Tutorial - HTML Basics

CSS

Using Cascading Style Sheets

Javascript

Javascript Kit
DHTML Document Object Model