and your novel is set in a realistic time, so you don't want the readers to be thrown out of the narrative by a name that completely jars with the time period. (Because, to be honest, there were not a lot of "Jaiden Waitara"'s in 17th Century London)
There are innumerable resources around the place to give you an idea on names. As I'm currently working on early 19th Century Cheshire,
here's how I did it.
Originally, I'd thought of "Abigail Mulgrew" for my village lass-turned-house-servant, but upon checking to make sure the name is plausible for the area, I googled "Origin of name ....". For Mulgrew, oh my. It's Irish. (I honestly had no idea). That will be useful if I need an Irish character, but I'm afraid my lass is about to be renamed. Right - let's do this properly.
First, my characters, while living in the Regency period, were born before it. I decided to start with what would probably be an authentic surname, so I looked up the current-day Business Directories for Chester, and picked a few surnames that sounded good. In particular, I liked Stanton, Kelsall and Gibson. Then check them to make sure they weren't created in the last 150 years. You could get away with a stray French or Spanish surname, perhaps, as there were people wandering all over the world, but you don't want a surname like "Mountbatten" for someone from the early 1800s (it was Anglicised from the German "Battenberg" in 1917).
All right then - "Kelsall". It turns out it's the name of a
really pretty village in the area. Perfect! There are some variations (such as Kelsaw) which might be useful for other things, so I keep it in the list. Even if it's a little way from where my novel is set, it would not be unreasonable for an ancestor of my lass to have moved to the novel's area some centuries before, which would doubly count for why they were named after their old home town.
Next, finding a good first name. I've discovered a site with the parish records of Cheshire, and am going to search by "Smith" as it's an all-over-Britain common surname. I plug this into a
genealogy site, and narrow down by birth century = 1700s and location = "UK". (If you're looking for modern day, plug a common surname such as "Smith" into your work directory, and look at the first names - but of course then choose a different surname to go with it.)
Not surprisingly, I've got thousands of options, but if I then narrow the search to Cheshire, I can cherry-pick those names. I can choose to take names that were from 1750 onwards, to try not to be too old-fashioned, and here's a short list I grabbed for the sake of the exercise: Nancy, Phebe, Sarah, Anne, Felina, Mary, Elizabeth, Susannah, Hanneh, Catherine, Betty, Charlotte.
I love that a lot of these are names that people use today, although some seem old-fashioned. I'm also thrilled to see someone actually called "Betty" rather than "Elizabeth". And the name Felina comes from the Latin meaning "Cat-like". Not quite right for my lass, but could be useful later.
So Abigail Mulgrew is now Susannah Kelsall. Two last things to do. First, I google on the name generally, to see if there's been anyone real by that name. There has, but no-one that seems to have changed the history of the world or so. You'd be hard pressed to find any realistic-sounding name that didn't already have someone of that name around the world somewhere.
More importantly, considering my novel, am I maligning any real nobility from the UK? I check the surname against the
Peerage lists and get a Captain in the Navy, a lady who married a baronet, and a few other assorted people. Obviously, everyone is important, but none of these people are members of the aristocracy or such, and there's no Susannah Kelsall that will be mortified if I put her namesake in my story.
Of course, if you get to publishing stage, a good editor will have a fact-checker (or be one themselves) to make sure that the fictional Earl is not named after one of the actual Earls of history. But it always helps to check first, too.