Not one stop shopping ...
There's no one place to search for newspaper articles. We have three huge newspaper databases, described below. They are all rather difficult to use. You will probably want to search news in a geographically narrow area. The first thing you need to do is figure out the names of the major news sources covering that area. The quickest way to do that is to do a Google search in this format: CITY STATE news
Then scan those results for the names of publications that look useful. Often you can search right there on their websites! But, you can also then use the library's list of Journals & Magazines to find out which database searches that specific newspaper.
If you were to search the San Francisco Chronicle, for example, you would find different years are searchable in different databases:
Searching Nexis Uni (formerly LexisNexis)
Nexis Uni includes a lot of things other than typical news sources. But, it is a great place to search news as it includes about 5,000 different news sources from around the world.
When it opens you will want to work in the area labeled GUIDED SEARCH and follow the pattern you see here:
Select News. Compose a search statement with these two labeled parts. The 1st part, labeled LEAD, is where you put words or phrases you think would appear in the lead paragraph, or beginning, of the story and enclosed in parentheses. Use * to truncate words. Put " " around phrases. Put the word and between different words/phrases. Keep it short, though. Then add the Boolean AND. It is a good idea to specify the LENGTH of the story. >1000 will only get you stories of real substance, but you can choose the length you want! You can then either select a date range from the pulldown or enter one of your design.
Once you have run the search, options to narrow the results appear in a column to the left. LOCATION and PUBLICATION TYPE are two you might want to have a look at!
Searching ACCESS World News
ACCESS World News has articles and broadcast transcripts from about 1000 different news sources from all over the United States as well as 150 other countries. While there are major newspapers that are conspicuously absent, like the Los Angeles Times or Chicago Tribune, all 50 states are pretty well represented. The dates of coverage vary from paper to paper. The tips for searching below will be time well spent. The details are critical!
TIPS for SEARCHING
Immediately click the 
button below the large search box. Notice you can specify sources geographically right below the search boxes. You can also do that after searching ... limits appear in a column to the left of the results.
You have to really think about your language when searching a fulltext newspaper database like this. Most of the time you will want to use your Select a Field option in the top box to specify Lead/First Paragraph. Try to think of specific words or phrases that are likely to appear at the beginning of the story you are seeking. Put " " around phrases. Use the asterisk to truncate for different word endings.
Use the 2nd box to put in Date(s).
And, you probably will want a 3rd search box to use to select the longest Word Count option to be sure to get stories of some substance!
If I were looking for a substantial story, for example, on efforts to ban plastic straws, I might do this search:
You really need to plan on trying different search words and you also need to take your time scanning results. The best story is not really likely to pop-to-the-top. You need to browse for it.
Searching Factiva
Factiva has full text articles from newspapers and magazines as well as transcripts of broadcast media from all over the world. While the main audience for Factiva is the business community, this is our most complete database for foreign newspapers. International coverage, including material in foreign languages, is far more extensive than NexisUni. You can be very specific about the geographic area of your source as well. Items are updated constantly in the case of news wires and daily in the case of most everything else. Retrospective coverage varies from title to title, but some go back to the 1980's. Change the DATES (very carefully!) unless you just want the most current 3 months. Below the big search box, you can select SOURCES from a specific region or select a REGION of interest. Connect words and phrases using AND, OR & ( ). The default is to look for those words anywhere in the article. You can require the words or phrases to be in the Lead Paragraphs (1st 2 paragraphs of the story) by putting LP= in front of the word/phrase. Another thing you might want to do is specify the length of the story to just get in depth stories. Do that by adding this phrase to your search: wc>800. So, for example, a search for long stories about homelessness in San Francisco would look like this:
LP=san francisco AND LP=homeless* AND WC>800