I have noticed that taking photos in bright Texas sunlight on my Canon T3i with a 50mm f/1.8 lens results in a blueish look over the whole photo. Someone said that a UV filter would help to remove some of that — is that true?
It would really depend on what UV filter you used. Not all UV filters are created equal, and even ones that are supposedly "high-end" might not function correctly, while some cheaper ones function quite well.
The ultimate goal of a UV filter is to filter out ultraviolet light, which starts around 380nm, and progresses on down to as small as 100nm or so. A quality UV filter will usually stop "filtering" right around 380nm, and be mostly transparent to all other wavelengths of light after that. A poorly designed UV filter may also filter some blue light, and may gradually taper off "filtering" up to around 420nm or so. Really poor UV filters will often also filter some amount of all wavelengths of light, some more green than others, acting as a very slight ND filter as well.
This article provides an excellent review of numerous UV filters. It is a little dated, however its process is very solid, and it covers how well each filter blocks just UV light (or not).
Your Canon T3i is a DSLR, so you do not really need to use a UV filter unless you really need to block excess UV light (most CMOS sensors are sensitive to some degree of UV light, however normal glass as used in camera lenses tends to block most of it.) You can always change the "White Balance" setting of your camera and adjust it more for an orange tint (lower K number). If you would prefer to optically control the color balance of your photos, you could use skylight or coral filters. Skylight filters come in several degrees of tint and will "cool" the tone of light (make it more blueish), while coral filters which also come in several degrees of tint will "warm" the tone of light (make it more orangeish.) Skylight and Coral filters are really a thing of the past these days, as many of the limitations of film no longer exist with digital cameras.