One great way to think about some baby names is to check out some trends from the past century. Every year, the Social Security Administration publishes a list of the Top 100 Baby Names that you can search and use for ideas. It's interesting to watch the trends -- there's a lot to be said for being able to predict a decade based on the kids' names from it, and this neat little website lets you search based on decade as well as by state, and popular names for twins.
You can also search to see which names are gaining popularity or losing popularity. For example, in 2009, two very popular names, Isabella and Jacob, can almost directly attribute their rise in popularity due to the "Twilight" series of books and movies, along with with the less common but gaining fast "Cullen" (Edward's last name). And for any given name, you can look up its trend -- for example, Samuel as a baby boy's name has been in the 20's on the Top 100 Baby Names list each year in the past decade.
So, what have been the top 100 baby names over the last 100 years? Here's the whole list from the SSA, with rank and number of babies given that name, so you can see where your baby name choice falls. It's also interesting to see just how many males make up the top 10 as opposed to the females -- I guess there's just more variety in female names!
Some baby names are perpetual favorites -- for example, boys' names like Michael and Joshua have been in the top 10 for 50 years or more. Other names fluctuate a little more widely though -- names like Christopher and Andrew, which seem like they might be fairly common, have fallen out of the top 10 in the last few years. Girls' names are even more fickle in trends -- Emily and Emma have been right up at the top of the list for quite a while, but other names like Jessica, Hannah, Ashley, and Sarah have dropped out recently in favor of names like Isabella, Olivia, Chloe, and Mia.
It's also always possible to name your child an interestingly different spelling of one of these popular names or to have the full name as the given name and use some shortened nickname in daily use. Elizabeth can be Liz, Beth, Betty, Betsy, Liesel, Liza, Lizzy, and so on. It's also nice to think about nicknames that can grow with your child -- if little Betsy wants to be Elizabeth when she grows up, her name can accommodate that. If you do choose a name from the Top 100 Baby Names list for your child, nicknames are key, because your baby will probably share that name with some other kids in school.