How can I print using my iphone 4s on my dell 1700 laser printer that is connected to home network

Directly from your iPhone, no. Apple supports a very select few printers that can print directly from the iPhone. My canon printer isn't supported for wireless printing, but canon has an app in the app store that allows me to print out photos at least directly from my phone.

If you want a printer that prints directly from your iphone (Apple calls it airprint) these are the models.

http://store.apple.com/us/browse/home/shop_ipad/ipad_accessories/printers Shop around sites like Amazon usually have them much cheaper then the Apple store.