For all those things, check out the coupon forum and then use the links provided because they help support the forums. As for lighting, it really depends on what you need (run time, brightness, to see, to be seen, helmet mount, handlebar mount, etc...). At the very minimum get a red blinkie for the back and a white blinkie for the front. I'd get a topeak road morph for a pump because it has the built in gauge. At least for one on the go. As for a bike kit, topeak makes a wedge for the saddle.
Congrats on getting the Downtube, tons of resources in the Downtube thread. I love mine.