I concur. A resume without an address seems weird. Even though no future employer is going to mail you a card to invite you to an interview (or at least I hope not o.O ), listing an address – or at least city, state, zip – is still very standard.
Since most people didn't answer about the cover letter, I just want to add another post echo'ing MLA's to say that the cover letter is extremely important. It needs to be at least somewhat personalized to the company and position you're applying for, too. Also, as “duh” as this may sound, make sure you never ever send the cover letter for one company to a different company. I have seen this many times. Makes you look extremely careless. (“I'm excited to discuss the opportunity to be a cook at Mom's Diner!” Well that's great, but you're applying to be an accountant at _____. Doesn't look good at all.) I would say minimum personalization for a cover letter should be to address it to the company (following standard business letter format – company name and address at the top of the letter) and name of individual if possible, and to include the specific position you're applying for within the body of the letter (“I'm writing to express my interest in the opening for a Staff Accountant”). A common thing in cover letters is to list where the job posting was found, but I'm not sure what value that adds, so I'll leave that to personal discretion. If you're willing to put some extra effort into your cover letters, though, one thing that really sets you apart is if you read through the job description and tailor the skills and qualifications mentioned in your cover letter to those requested in the job posting. Maybe the job posting asks for something unusual that you have. Don't make them read the resume to find out you have it; mention it in the cover letter.
Also, keep your cover letter short. I know, I know, I just said to say all these great things in it, now I say keep it short? It's a difficult balance. My standard cover letter format has a short intro paragraph (2 or maybe 3 short sentences), a bullet list of relevant skills (4 or 5, briefly stated – “Expertise in Microsoft Excel”, not “I have extensive knowledge in Microsoft Excel, and am skilled with Vlookups, Pivot Tables, SumIfs, and many other tools, as well as possessing the ability to quickly learn new Excel formulas as needed to complete projects”), and a short closing paragraph. Your cover letter is a piece of marketing material. It's an advertisement of sorts. In marketing, I've heard that they say you have 30 seconds to sell a product to through written medium to your audience; after that, you've lost them. So, if you say lots of really good things in a cover letter, but it takes 3 minutes to read, you're not getting anywhere. You want something that they can at a glance see what's important (which is why I use a bullet list of my skills, which are tailored to their job description – hoping it pops out at a glance “Oh, she's got skill balancing spoons on her nose like we asked for!”), and within 30 seconds or so they can read it all and be hooked, and “drawn in” to read through your resume.
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