Advice for study

Hello guys, this is my first post on chess.com! I guess I would consider myself to be a novice player (FICS rating is on average around 1250). I've recently begun to study Logical Chess Move by Move as well as Laszlo Polgar's huge collection of tactics. I've been studying intently for about a couple months but I haven't noticed much improvement. Does anyone know of any good tactics books for someone in my range. The Polgar collection is around my level but unfortunately most of the exercises are mates in a couple moves. I'm kind of looking for a book that emphasizes tactics in the context of positional play. 

Another skill I really want to work on is my ability to come up with solid moves in my games. One of my main weaknesses is that I can't really evaluate my position when it becomes more dynamic. A book recommendation for purely positional training would be much appreciated.

Thanks in Advance

A few recommendations:

Tactics:

- Winning Chess Exercises for Kids - Coakley (Actually tougher than the title sounds!)

- Practical Chess Exercises - Cheng

Positional primers: 

These don't overload your brain like some of the older/Russian books do ... I've found them a much easier place to get my feet wet before hitting the heavy stuff.

- Simple Chess - Michael Stean

- Best Lessons of a Chess coach - Weeramantry

You can't go wrong with a chess.com paid  membership either. NM Dan Heisman's Novice Nooks (they are free!) are also a gold mine for your level.

tactics: try either "tactics trainer" on this site or chesstempo.com

as for coming up with solid moves: i don't know a specific book, but i'd recommend playing through GM games and trying to guess at the next move before you look at it.