Here is another link to Zyzzyva, another useful word searching software.

Here I have some tips for playing Scrabble. Firstly, on the opening move, it would be wise to try not to place a vowel in the line of the four double letter premium squares, as an opponent could take advantage of it and place a word parallel to yours, scoring quadruple the score of his high valued consonant. Of course if to play a pretty high scoring word like a bingo would mean exposing a vowel to a double letter square, it would be acceptable to open up such spaces. The "safest" vowels to play, in order, would be U E I A then O. Also, try not to play the opening word where it can easily be changed into a "triple word tile reaching" word with the addition of a prefix or suffix.

Next, you should play more aggressively if you have a good rack and more defensively if you are drawing bad tiles. Of course, try to keep certain tiles in your hand for a higher chance of a bingo. Try to play duplicate letters, and the best tiles to keep are...

Vowels: blank E A I O U in order.
Consonants: blank S R T N L D G M P H B W Y F C V K X J Z Q in order.

It is a good idea to try and maintain a 3:4 ratio of vowels to consonants in your hand.

Your opponent will often score well as a result of a tile you put. Try not to open triple word bonuses. If one is open and you have no good word to play on it, you should consider opening another triple word premium square, that may give you a chance after your opponent moves. Playing a word parallel to a word already on the board will gain you points for the word you played, as well as the two/three letter words you form along the way.

Another thing, look out for the double word scores that have five tile space in between as they can quadruple the score for your whole word if you reach them both in one word. Those with seven tile space in between can still be reached with the aid of a two-letter word on the board.

At the end-game try to remove of hard-to-play letters like Q and V. If your opponent is caught with them, try not to open an opportunity for him to dump it. If you have C P A U in your hand, playing CUP would be better than CAP as a sole A is easier to discard than a U. If there is a word such as QUESTION on the board and the blanks have been played as well as three Ss, the bag is empty and you do not have the last S, try to play a word sprouting from a two letter word with the N, so though your opponent has the S, it cannot be played there for a handsome score.

Hope you found this useful!
Have fun!

Hello! Here I have some links to stuff Scrabble enthusiasts would be interested in.
Here is the link to download Lexpert. Its a software that helps you find words, though its list does not contain some words accepted by TCWL. Still it is quite useful.
This is the link to ISC, which stands for Internet Scrabble Club, you can sign up for free and play against opponents from around the world, with adjustable time limits and challenge rules.
Have fun!