This page contains links to all of the puzzle solving tools I featured as bonus blogs in 2011 (except in a couple of cases where I know those sites are no longer functioning) along with a couple of new sites I've found since then. I'm listing them in the reverse order they were published, but will add a * next to the ones I find myself using most often. As always, please exercise caution in downloading any files from the internet. These are sites I have used successfully in the past but unfortunately I can't guarantee the safety of any particular site.
The basics ... Google is your friend, and lots of puzzles were created using Wikipedia
*Wolfram Alpha incredibly useful site for anything mathematical or number related
Digital Root Calculator for Words calculates the digital root of word or phrase
Geocaching Toolbox multipurpose tools (lots in there ... worth some time exploring)
Audacity free downloadable tool for analyzing/editing sound files
*GIMP free downloadable image processing tool
*Cryptocrack powerful free downloadable cipher solver
*What's This W?rd? very useful crossword puzzle solving tool
How To Puzzle Cache this is the facebook page for Cully Long's new (and very useful) book.
*Google Images powerful tool for searching images
*Victor Image Processing Library, Online Image Processing analyze & compare images
The GPS Resource Library mapping tools & info
Martindale's "The Reference Desk" multipurpose reference site ... lots of topics
Transliteration transliteration tool in 15 different languages
Puzzle Sequences questions/answers and links to interesting number sequences
*BION's cipher page tools for advanced cipher solving
*Decrypto 8.5, Online Cryptoquip and Cryptogram Solver cryptogram solver
*Jeffrey's Exif viewer get image properties from images
Mathematical Constants Search search mathematical constants pi, e, or the square root of 2
*Number Bases Conversion Tool; Bases 2 - Base 64 Converter converts between mathematical bases
DialABC - Tools for Phone Numbers phone number tools (including audio tools for touch-tones)
AltaMatic - Empowering Amateur Detectives tools for researchers/historians/detectives/puzzlers
1728.org multipurpose site with lots of tools ... lots of fun to explore. Scroll down past all the ads.
Black Chamber Vigenere Cracking Tool from the author of The Code Book
Number Cruncher Everything you ever wanted to know about a particular number
Unicode Character Search look up unicode characters
Alt codes list list of "alt" codes
*American Cryptogram Association: Cipher Types parameters for different ciphers with examples
*Anagram Solver anagrams your input ... not perfect but can be quite useful for proper nouns.
ASCII, Hex, Unicode, Base64 Converter/Translator convert between formats of letters/numbers
Frivolities | Basketball-Reference.com Lots of fun info about basketball players
*Omniglot: the guide to languages, alphabets, and other writing systems - historical/literary/constructed alphabets.
The Number Empire lots of numerical tools
Basic Cryptanalysis lots of educational information
*More Words play with this tool and see how much it can do with words
*GPS Visualizer's Coordinate Calculators and Distance Tools lots of useful map-related calculators
List of Numbers in Various Languages
downloadable version of google maps. Also includes maps of the moon, Mars, and the stars.
Geocaching Quick Search search the geocaching.com site in a variety of ways
I'd Rather Be Caching: Solving Puzzle Caches tips on puzzle solving
Parmtro's Geocaching Pages: Solving Puzzles more tips on puzzle solving from another cacher
CIA World Fact Book statistics, maps, flags, etc.
Sports Database teams, players, jersey numbers, etc.
The Internet Movie Database all kinds of data about movies, tv shows, actors, etc.
Geocaching | Puzzlehead tips on solving and creating your own puzzles
Secret Code Breaker tools and links to other tools for solving codes
*Convert Coordinates converts between different coordinate systems
Useful Websites for Puzzle Solving another cacher's recommended websites
Puzzle Tools and Resources general tips and tools (not by cachers)
7 Mystery and Puzzle Ideas more tips by cachers
ASCII Alphabet Characters list of ascii codes for alphabet (links to codes for numbers as well)
*ASCII Translator translates to/from ascii in several formats
Binary translator from ascii text to binary and from binary to text converts binary ascii
*Google Translate translates to/from many languages
Purple Hell Riddle Tools (Archived) lots of good tools ... original site no longer available
ZXing Decoder Online online barcode reader
*Iterative Anagram Solver my go-to site for creating and solving anagrams
Morse Code Translator translates to/from Morse code
CipherClerk online solving tool for medium-level ciphers
Encryption Resources - ROT to any number, image search, and Vigenere cipher tool