The Beit Yosef (OH 46) notes that this blessing is not found in the Talmud. In Be'ur HaGra to Shulhan Arukh (OH 46:6), the Vilna Gaon comments on both the opinion of the Shulhan Arukh, who states that it does not appear that one should make the blessing, and on the opinion of the Rema, that it is a common Ashkenazi practice. He does not clearly prefer one position, and explains both.
However, the work Ma'aseh Rav (Tosefet: 2) (cited in Yabia Omer II:25:12) states the Vilna Gaon personally did not recite the blessing.
An additional example of a non-Talmudic, yet popular blessing, is שעשני כרצונו, recited by many women, which is not Talmudic as noted by the Taz (OH 46:4).
Also, the blessing מקדש את שמך ברבים (or variations such as מקדש שמו ברבים) which is a popular blessing that is not found in the Talmud, and is based on a Yerushalmi (that states that angels say it), see Tur (OH 46).
- The blessing ברוך ה' לעולם recited before the Amida of Maariv by many, which is of questionable origin (see this Hebrew article).
- A blessing recited by many fathers upon the Bar Mitsvas of their sons: ברוך שפטרני מענשו שלזה which is not found in the Talmud (see here). Rather it is based on a Midrash (which isn't necessarily endorsing a formal blessing either, see Genesis Rabba 63:1).
- A blessing (harshly opposed by Rambam who describes it with revulsion in Responsum 207, ed. Blau) upon the consummation of marriage with a virgin. This blessing is nevertheless cited by Tur (EH 63), and referenced by the Shulhan Arukh and Rama there, and is later endorsed (albeit without the recitation of God's name), by Hokhmat Adam (Sha'ar Beit HaNashim 115:18).
- The blessing on candles for Yom Tov, which is not found in the Bavli, although it is defended based on some editions of the Yerushalmi, see Hagahot Maimoniot to Hilkhot Shabbat (5:1). This blessing is mentioned in the Shulhan Arukh (OH 263:5), and is quite popular.
- The blessing for candles on Shabbat is not found in the Talmud, and was thought by some such as the historian Isaac Hirsch Weiss to have been invented by Rav Natronai Gaon to oppose Karaites who did not allow fires burning in their households. It is possible that the Geonim had a tradition about the existence of this blessing received from the Talmudic sages, although it does not seem to have been unanimous among the Geonim, and was disputed on medieval France. see R. Rasson Arussi's article in Sinai (85 pg. 60). This blessing is quite popular and is mentioned by Rambam (Hilkhot Shabbat 5:1) and the Shulhan Arukh (OH 263:5).
- There is also the famous Barukh Sheamar blessing, which is not mentioned in the Talmud, see discussion about its provenance here.
A blessing דיין האמת recited upon ripping one's clothes in mourning (as distinct from upon hearing of their deaths). This blessing has no clear Talmudic basis (see Hida's Shu"t Hayyim Sha'al II:38:47 and Shu"t Melamed L'hoil II:YD:105).
Many other particular mitsvot do not have their berakhot listed in the Talmud, and many Rishonim laboured to find a system to explain which mitsvot customarily have berakhot and which do not. One example of a disputed mitsva is that of tevillat kelim (which is either a biblical or rabbininc commandemnt). Like most mitsvot, it is not specifically mentioned in the Talmud. Teimanim did not say it (R. Qafih's Ketavim, Vol. II: pg. 556), although many other do, see Tur (YD 120), and Shulhan Arukh there (3).