What "extra" ingredients to use?
 

I am planning on brewing a 5 gallon bach of ale with extract (DME) and have heard of adding other ingredients that help with the presentation of the beer, like Irish Moss for cloudiness or gelatin for something?

Is there additives like this that should typically used for every bach of beer that i brew and at what part of the bowl would i add them?

If you are doing extract brew, I wouldn't worry about the clarity too much. Most of what causes clarity issues has been removed during the manufacture of the extract. It's more of an issue if you are using grains. If you do use irish moss, usually a teaspoon is added in the last 15 minutes of the boil.

Irish moss or a Whirlfloc tablet (refined Irish moss) is really all you need to add, if anything.

Other finings can be added to the fermenter, but they tend to strip a bit of flavor/body from your beer. Gelatin is the worst when it comes to flavor stripping, and Polyclar or Isinglass supposedly clarify more "gently."

Generally, you should try to avoid "additives." One of the reasons to brew your own beer is to have control over what goes in it. (Or, better yet, was doesn't go in it). While you certainly don't need to adhere to the German beer purity laws, in general simple is better. When you are making 5 gallon batches you can afford to put only the best of ingredients in your beer. I use Irish moss, but that's about all that goes in my beer besides water, yeast, malt and hops. I may eventually try a pumpkin ale or a raspberry or something like that, but mostly I just want to make good beer.