If you were to simply type in the phrase "buy stock photos" into Google or Yahoo's search engine you'll be hit by literally thousands of places offering to sell you their images.
In fact, out of those thousands many will promise to be the best. But how do you really know the best place to get your images from, what image size to select and if the image quality is worth it?
Image sizes typically range from an extra small size of 281 x 472px, or about 3 X 4 inches, right up to an XXlarge at 4550 x 3742px, or about 15 X 12 inches. The size you'll need really depends on what you intend to use it on.
For example, most of my graphic work that requires purchasing stock photos can be done using 380 x 320, about 5 X 4 inches (or similar). I've used this size image to liven up my header graphics, customize banners or add a nice image to content on my website.
If you're looking to add images to your website, eBook, newsletter or other online media then you will rarely need a size larger than what I've used in the past. If you're looking to download an image for print then you'll want to consider your end use.
One thing to remember, the larger the original image is the better quality it will be when making changes to it.
Determining image quality leans slightly on the complex side for those of us unfamiliar with the digital photo industry. If you were to ask an experienced photographer they will tell you to look for resolution and dpi, whatever those are! But there is a way for the rest of us to determine image quality.
First, view the image in the full size you plan to purchase. This is typically done by clicking on the image itself. If it's clear and smooth in appearance you can mark it as a quality image. Another method would be to print it out, however, I don't think you will find that option before purchasing the actual photo in most cases, but if you can see how it looks when printed.
Another excellent way to know if images are of good quality would be to read the reviews. A website that has a consistent record of positive reviews is a safe bet on a good image. Additionally you can contact the webmaster and ask if they have any free images you could download to see the types of images you'll be purchasing.
When considering who to buy your images from you want to do your homework diligently. With so many options out there you're at a higher risk of getting photos of low quality or no quality at all for that matter. When evaluating websites here are a few things to keep in mind:
Perhaps the most important tip I can give you is this; when you're ready to buy stock photo online don't go at it in the dark. Familiarize yourself with the different sizes and their uses. Choose a handful of popular stock websites and compare their prices and package discounts so you'll know if the pricing you find is fair.
Finally, understand the current copyright laws so these cheap webmasters can't scam you into paying full price for limited use. By sticking to these tips you'll be armed and ready when it comes time to make that purchase.